English

Model Checking Positive Equality-free FO: Boolean Structures and Digraphs of Size Three

Computational Complexity 2008-08-06 v1 Logic in Computer Science

Abstract

We study the model checking problem, for fixed structures A, over positive equality-free first-order logic -- a natural generalisation of the non-uniform quantified constraint satisfaction problem QCSP(A). We prove a complete complexity classification for this problem when A ranges over 1.) boolean structures and 2.) digraphs of size (less than or equal to) three. The former class displays dichotomy between Logspace and Pspace-complete, while the latter class displays tetrachotomy between Logspace, NP-complete, co-NP-complete and Pspace-complete.

Keywords

Cite

@article{arxiv.0808.0647,
  title  = {Model Checking Positive Equality-free FO: Boolean Structures and Digraphs of Size Three},
  author = {Barnaby Martin},
  journal= {arXiv preprint arXiv:0808.0647},
  year   = {2008}
}
R2 v1 2026-06-21T11:07:43.027Z